1 files changed, 99 insertions, 0 deletions
diff --git a/packages/backend/src/core/ImageProcessingService.ts b/packages/backend/src/core/ImageProcessingService.ts
new file mode 100644
index 0000000000..d215be2131
--- /dev/null
+++ b/packages/backend/src/core/ImageProcessingService.ts
@@ -0,0 +1,99 @@
+import { Inject, Injectable } from '@nestjs/common';
+import sharp from 'sharp';
+import { DI } from '@/di-symbols.js';
+import { Config } from '@/config.js';
+
+export type IImage = {
+	data: Buffer;
+	ext: string | null;
+	type: string;
+};
+
+@Injectable()
+export class ImageProcessingService {
+	constructor(
+		@Inject(DI.config)
+		private config: Config,
+	) {
+	}
+
+	/**
+	 * Convert to JPEG
+	 *   with resize, remove metadata, resolve orientation, stop animation
+	 */
+	public async convertToJpeg(path: string, width: number, height: number): Promise<IImage> {
+		return this.convertSharpToJpeg(await sharp(path), width, height);
+	}
+
+	public async convertSharpToJpeg(sharp: sharp.Sharp, width: number, height: number): Promise<IImage> {
+		const data = await sharp
+			.resize(width, height, {
+				fit: 'inside',
+				withoutEnlargement: true,
+			})
+			.rotate()
+			.jpeg({
+				quality: 85,
+				progressive: true,
+			})
+			.toBuffer();
+
+		return {
+			data,
+			ext: 'jpg',
+			type: 'image/jpeg',
+		};
+	}
+
+	/**
+	 * Convert to WebP
+	 *   with resize, remove metadata, resolve orientation, stop animation
+	 */
+	public async convertToWebp(path: string, width: number, height: number, quality = 85): Promise<IImage> {
+		return this.convertSharpToWebp(await sharp(path), width, height, quality);
+	}
+
+	public async convertSharpToWebp(sharp: sharp.Sharp, width: number, height: number, quality = 85): Promise<IImage> {
+		const data = await sharp
+			.resize(width, height, {
+				fit: 'inside',
+				withoutEnlargement: true,
+			})
+			.rotate()
+			.webp({
+				quality,
+			})
+			.toBuffer();
+
+		return {
+			data,
+			ext: 'webp',
+			type: 'image/webp',
+		};
+	}
+
+	/**
+	 * Convert to PNG
+	 *   with resize, remove metadata, resolve orientation, stop animation
+	 */
+	public async convertToPng(path: string, width: number, height: number): Promise<IImage> {
+		return this.convertSharpToPng(await sharp(path), width, height);
+	}
+
+	public async convertSharpToPng(sharp: sharp.Sharp, width: number, height: number): Promise<IImage> {
+		const data = await sharp
+			.resize(width, height, {
+				fit: 'inside',
+				withoutEnlargement: true,
+			})
+			.rotate()
+			.png()
+			.toBuffer();
+
+		return {
+			data,
+			ext: 'png',
+			type: 'image/png',
+		};
+	}
+}